751 Background: The Lyon R96-02 randomized trial has demonstrated in T2-3 rectal cancer that external beam radiotherapy (EBRT) with Contact X Ray brachytherapy (CXB) boost was increasing clinical complete response, sphincter preservation and in early cases organ preservation. We report French experience in 3 radiotherapy departments using CXB boost with chemoradiotherapy (CRT) in early T2T3N0. Methods: Selection based on digital rectal examination, colonoscopy, MRI (and/or Endorectal-ultrasound). Inclusion : adenocarcinoma (distal, middle rectum), T2 T3a-b, tumor diameter ≤ 4cm, N0, M0. Treatment : CXB (80-110 Gy/3-4 fr) followed by CRT (CAP 50). Tumor response assess on week 14 : DRE, rigid rectoscopy and MRI. Clinical complete response (cCR) defined as no visible tumor, supple rectal wall and TRG 1-2 on MRI. In case of cCR a close surveillance or local excision was proposed. Results: Between 2002 -2016, 84 patients treated. Median age: 75 years, Male: 59, Female: 25. Operable patients: 69 (83%). T2 : 52, T3 : 32 (Lyon Villeurbanne : 16, Macon : 11, Nice : 57). Median follow-up time : 53 months. cCR was achieved in 94% of cases. Local excision performed in 17 patients (ypT0 : 16). At 4 years, the cancer specific survival was 82% [CI:96-70] and the local relapse rate 12% [CI: 2-22]. No isolated perirectal lymph node relapse observed. After 4 years, 3 more local relapses observed (4, 6, 7 years). Main late toxicity ( > 6 months after treatment) was rectal bleeding (radiation telangiectasia) which required plasma argon coagulation in 5 patients. No TME surgery was performed and organ preservation was achieved in all cases. Bowel function was good in 85% of patients (LARS score < 20). Conclusions: When combining CXB with CRT, rectal cancer T2T3a-b N0 ≤4cm achieve a high rate of cCR (≥85%) with organ preservation, good bowel function, low rate of local relapse ( < 15%) and low toxicity. As rectal adenocarcinoma is radioresistant, the treatment must use a CXB boost. Like anal squamous cell cancer, planned organ preservation can be proposed to operable patients. The ongoing European OPERA trial aims at bringing evidence to this option.
What Should Be Considered for Local Excision in Early Rectal Cancer?
